Reputation: 25873
I have the following override of method on hashCode
in AbstractORM
class:
var _id = Random().nextLong()
override fun getId() = _id // AbstractORM class implements an interface that defines this method getId()
override fun hashCode() = getId().hashCode()
which suddenly started to throw the following exception:
FATAL EXCEPTION: main
java.lang.NoSuchMethodError: java.lang.Long.hashCode
at com.company.ormlite.AbstractORM.hashCode(AbstractORM.kt:271)
at java.util.HashMap.put(HashMap.java:390)
at java.util.HashSet.add(HashSet.java:95)
at kotlin.collections.ArraysKt___ArraysKt.toCollection(_Arrays.kt:6518)
at kotlin.collections.ArraysKt___ArraysKt.toSet(_Arrays.kt:6853)
at kotlin.collections.SetsKt__SetsKt.setOf(Sets.kt:32)
at com.company.android.tna.orm.DataManager.getTables(DataManager.kt:16)
at com.company.android.tna.orm.DataManager.getTables(DataManager.kt:10)
at com.company.android.core.utils.AbstractDataManager.create(AbstractDataManager.kt:25)
at com.company.android.core.utils.AbstractDataManager.start(AbstractDataManager.kt:44)
at com.company.android.core.utils.AbstractZKApplication.onCreate(AbstractZKApplication.kt:54)
at android.app.Instrumentation.callApplicationOnCreate(Instrumentation.java:999)
at android.app.ActivityThread.handleBindApplication(ActivityThread.java:4151)
at android.app.ActivityThread.access$1300(ActivityThread.java:130)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1255)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4745)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
This has me dumbfounded for several reasons:
hashCode
method since it is inherited from Object
or Any
.kotlin.Any.hashCode
, not to java.lang.Long.hashcode
.Any insights would be greatly appreciated, thanks in advance.
Upvotes: 22
Views: 5259
Reputation: 932
I've encountered the same issue and the solution for me is to assign both compileOptions
and kotlinOptions
in build.gradle to version 1.8
android {
...
// Configure only for each module that uses Java 8
// language features (either in its source code or
// through dependencies).
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
// For Kotlin projects
kotlinOptions {
jvmTarget = "1.8"
}
}
Referenced from Use Java 8 language features of Android Developers official website.
Upvotes: 3
Reputation: 106
Overriding the hashCode()
function, as m0skit0 suggested, worked for me. I implemented this:
override fun hashCode() : Int = id.toString().hashCode()
My Kotlin compiler setting in AndroidStudio is :
Upvotes: 5
Reputation: 25873
After checking the compiled AbstractORM
class I found the problem: newer Kotlin versions generate a different code for that line
getId().hashCode()
Kotlin 1.1.2 generates the following code:
Long.valueOf(this.getId()).hashCode()
while newer versions of Kotlin generate this other code:
Long.hashCode(this.getId())
The problem is that this static method Long.hashCode(long)
in Android is only available since API 24 (Android 7.0), while I'm testing on an Android device that has version 4.1 (API 16).
I'm temporarily fixing by calculating the hash code manually although I've opened an issue here.
override fun hashCode() = (getId() xor getId().ushr(32)).toInt()
As commented on the issue, switching to Java 1.6 target for the Kotlin compiler generates the old compatible code.
PS: I'm not 100% sure about those Kotlin versions, please take with a grain of salt.
Upvotes: 19
Reputation: 11963
I'm not sure about how to solve your problem, but I'll try to explain why are you getting this exception.
In Java 8 a new static method was added to a Long
class:
public static int hashCode(long value)
And since then hashCode()
method looks like this:
public int hashCode() {
return hashCode(this.value); // call Long.hashCode() static method
}
So it seems that you have some issues with Java version.
Upvotes: 3